Buy one. You will want two.
It is not weakness, and it is not an accident. The pull to complete a set runs deep. Show someone four of something and a gap where the fifth should be, and their attention snags on the gap, not the four they already have. There is a name for this itch to finish what is started. The unfinished thing keeps a small open loop running in your head until it is closed.
Collectors know the feeling without the theory. The first piece is a purchase. The second is a pattern. By the third, you are no longer buying objects. You are building something, and a half-built thing wants to be finished.
The first piece is a purchase. The second is a pattern. The third is a collection.
This is where most of retail goes wrong. It chases the open loop with noise: drops you do not care about, badges, the fear of missing out on things that were never worth having. The loop closes for a second when you buy, then a new fake one opens. That is not a collection. That is a treadmill.
There is a better version. A set worth completing is one where every piece earns its place on its own. You would be happy owning just one. The fact that it belongs to a family is a bonus, not the bait.
That is how we think about a drop. Each object stands alone first: useful, personal, finished by hand. If it also sits beside others in a set, your team and your sister's team, your name and your kids' names, then good. The collection is the reward for caring, not a trap to make you care.
So use the instinct, but point it at the right things. Let your brain want the full set. Just make sure the set is worth finishing.